1. Field of the Invention.
The present invention relates generally to stagings, planks, scaffolds, or boards, and more particularly to a PLANK SUPPORT JACKET to avoid or minimize bowing, bouncing, or movement of the staging, plank, scaffold, or board it is supporting.
2. Description of the related art including information disclosed under 37 CFR .sctn.1.97-1.99
Heretofore, people have used scaffold boards or planks in conjunction with scaffold supporting devices. For example, a plank may be positioned with each end thereof resting on a selected step of a pair of placed supports to dispose the plank in horizontal supported position and thus allow work to be performed therefrom. In such a position, the plank may be subject to bowing or other bouncing or undesirable movement depending upon the length of the plank, the quality of the support structures, the weight placed upon the plank, and other factors.
In U.S. Pat. No. 2,808,296 to Stinson, there is disclosed a scaffold plank designed not to be liable to sag between supports upon which its ends rest when in use. This scaffold plank is formed of upper and lower sheets of plywood which are held in proper spaced relation to each other by longitudinally extending light metal rails, channel shaped and tapering to effectively secure the boards bowed longitudinally so that they are spaced from each other at a point midway between the length of the plank and converge towards the ends of the plank. The longitudinally extending rails comprise lightweight channels having webs tapering from a maximum width midway between the ends of the plywood sheets to a minimum width at the ends of the plywood sheets, the channels having flanges through which rivets may be passed to secure the plywood sheets to the rails.
In U.S. Pat. Des. No. 247,722 there is disclosed an ornamental design for a bracket support for a workman's plank providing a C-shaped bracket supported by legs to secure a workman's plank.
In U.S. Pat. No. 2,674,017 to Barnett there is disclosed a sheathing splice designed to secure the ends of two planks together by use of a sheathing splice cooperative with slots milled in the boards supported thereby.
In U.S. Pat. No. 1,687,706 to Bauer there is disclosed a reinforced scaffold plank wherein the plank at its underside is provided with a tension member, preferably in the form of a steel cable, anchored at the ends of the plank and adapted to be tensioned by means of a pivoted torsion bridge or cam element intermediate the ends of the plank.
The PLANK SUPPORT JACKET of the present invention comprises an upper horizontal ledge and a lower horizontal ledge joined to a vertical wall member, each ledge extending from the vertical wall member in a direction opposite the other, and means for connecting the vertical wall member to the longitudinal side surface of a plank to be supported thereby such that the lower horizontal ledge is disposed adjacent to the underside surface of the plank and the upper horizontal ledge is disposed in substantially axial alignment to the upper surface of the supported plank.
Such structure advantageously avoids or minimizes longitudinal bowing or bouncing or other undesirable movement of the plank independent of scaffold support structures or special ledges or brackets thereof, and requires no special milling of the plank of wood to be supported. Further, the present invention beneficially provides reinforcing means for a scaffold board or plank, so that the board or plank may be made of considerably less thickness relative to its length and yet have greater supporting strength. Still further, the upper horizontal ledge of the PLANK SUPPORT JACKET serves as a visual definition of the plank longitudinal boundary and also as a warning track to the supported plank. Preferably, the upper ledge is serrated to guard against slippage. Also, the the upper horizontal ledge of the PLANK SUPPORT JACKET may extend outwardly from the upper surface of the supported plank a sufficient distance to shield the means for connecting the vertical wall member to the longitudinal side surface of the supported plank thereby promoting safety of workers upon the plank by avoiding tripping on or entanglement of clothing or work materials with the connecting means.